A liquid crystal display (LCD) generally includes a liquid crystal panel and a backlight module oppositely disposed, wherein the backlight module provides display light rays for the liquid crystal panel so that the liquid crystal panel completes the display. A conventional backlight module is matched with the liquid crystal panel in some aspects such as size, spectral color, brightness, and the like, thus ensuring that the color and brightness, etc. displayed by the liquid crystal panel have a favorable effect.
Color filters of different liquid crystal panels have different materials, different thicknesses and different transmissivity. Even if different liquid crystal panels have a same size, different designs for backlight modules is also required. In the existing backlight module, mostly a light emitting diode (LED) and an Organic Light Emitting Diode (OLED) are served as basic light emitting units, wherein the LED emits light rays with different wavelengths in accordance with different fluorescent powders and light emitting chips; and the OLED emits light rays with different wavelengths in accordance with different materials.
Display light rays generated by different backlight modules have different wavelengths. The liquid crystal panel presents different colors by means of a picture displayed by the display rays. For example, regarding an all-white picture, different backlight modules matched with a same color filter will present different chroma, wherein the chroma is based on a CIE1931 system.
With the development of the market and industry, current panel manufacturers mainly produce and sale the liquid crystal panels. In general, backlight modules are individually purchased and assembled in a complete machine factory (for example, TV manufacturers). To a panel manufacturer, various tests like a reliability test or a lighting test and the like performed to a liquid crystal panel mainly use a backlight module. Different size liquid crystal panels mainly differ in color filters, transmissivity, and the like. Adopting an unchangeable display light ray may lead to incorrect chroma of a white dot of different liquid crystal panels, which may bring harmful influence to the various tests.